FORMIC ACID GEL-STRIP
      The application of formic acid to honey bee colonies for the
control of tracheal mites and varroa mites has been shown to be
generally effective and has been registered for use against these
pests in several European countries. However, the application of
liquid formic acid has several draw backs i.e. obtaining correct
dosages, potential hazards to the applicator and multiple
applications are required.
      Medivet Pharmaceuticals of High River Alberta is developing a
formic acid gel-strip to overcome these problems. Willy Baumgartner
of Medivet feels that the potential for a one shot application is
feasible. However, additional work is required to obtain a
formulation which will give the necessary control. Medivet has had
the cooperation of Dr. Don Nelson of the Beaverlodge Research
Station, Kerry Clark and Paul Van Westendorp of the B.C. Ministry
of Agriculture, John Gruszka from Saskatchewan Agriculture, and Dr.
Bill Wilson from USDA in evaluating initial formulations.
      The gel-strip is being developed to accomplish several
objectives at the same time; to provide a method that requires only
one application, to make the method of application easy and safe
for the applicator, and to provide more uniform evaporation over
the treatment period.
      How does the gel-strip work? The gel formulation has formic
acid incorporated into it. The gel is encased in a plastic tube
about 12 inches long and 2 inches wide with holes on one side,
which are covered by a sticky over-wrap. The gel-strips look very
much like the flavoured ice-cicles that your kids buy.
 
 
The gel-strip is stable, until the over-wrap is removed, which
exposes the formic acid gel to the environment. Thus, application
is easy: remove the over-wrap, place across the top bars of a bee
colony (holes downward) and replace the colony cover. The
evaporation of the formic acid takes place over a three week period
and with one treatment the colony receives the required amount of
formic acid.  Work is continuing to determine the proper
evaporation rate, which will deliver the required formic acid
dosage over the treatment period.
      Formic acid has been approved for use in Canada. The formic
acid gel-strip has given about 70% control of tracheal mites. A new
formulation is being evaluated this spring. Hopefully the level of
control can be increase to the same level as three weekly
applications of 65% liquid.
------------------------------------
contact D.L. Nelson for further information
Agriculture and Agri-Food Canada
Box 29, Beaverlodge, Alberta   T0H 0C0